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Synchronously Pumped Mode-Locked 1.89 μm Tm-Doped Fiber Laser with High Detuning Toleration

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Chinese Physics Letters 2018年第11期35卷 35-37页

作者：李根周勇李淑杰姚培军高伟清顾春许立新 Department of Optics and Optical Engineering University of Science and Technology of China

We propose and demonstrate a synchronously pumped mode-locked Tm-doped fiber（tdf） laser without any extra mode-locking elements. Pumped by a 1.56 μm pulse fiber laser, the tdf laser generates 1.17 ps pulses with a spectral width of 9.7 nm and a repetition rate of 9.33 MHz. The emission wavelength is tunable along with the cavity length detuning in a wide range of 3 mm. The high detuning toleration is beneficial to achieve high temperature and vibration stability in all-fiber configuration lasers.

关键词： tdf RBW kHz m Tm-Doped Fiber Laser with High Detuning Toleration Synchronously Pumped Mode-Locked 1.89 Tm

Performance evaluation of the use of tire-derived fuel fly ash as mineral filler in hot mix asphalt concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第2期7卷 249-258页

作者： Min Ju Choi Yong Joo Kim Hyeok Jung Kim Jae Jun Lee BILTZONE Co. Ltd.Hwaseong 18514South Korea Korea Institute o f Civil Engineering and Building Technology Goyang-Si 10223South Korea Industry-Academic Cooperation Foundation Center Hankyong National UniversityAnseong-si 17579South Korea Department of Civil Engineering Chonbuk National UniversityJeonju 54896South Korea

According to deplete natural resources and need to protect the environment,the demand of a usage of waste material has significantly increased.Many studies are currently being carried out on the development of innovative and environmentally friendly materials for securing the safety of road users and improving the performance and durability of roads.For example,studies are currently being conducted on the use of waste tires as a substitute for currently used fuels.Since the development of the automobile industry,the amount of waste tire has continuously increased in accordance with the increased vehicle numbers.Tire-derived fuel(tdf)has been used as a fuel source with generated tdf fly ash.Mineral filler,made of fine mineral particles of a physical size passing the number 200 standard mesh sieve(75 micron),plays an important role in asphalt mixtures properties.This paper presents an application of tdf fly ash as filler in hot mix asphalt(HMA).In this study,the performance of tdf fly ash was confirmed through a comparison with three other mineral fillers:stone dust,cement,and hydrated lime.Various tests including Marshall stability test,moisture sensitivity test,dynamic immersion test,and a wheel tracking test were performed to investigate the difference in the behaviors of the samples with different parameters considered in this study.The results show that the mechanical performance of hot mix asphalt using tdf fly ash satisfied the quality standard specification of the Ministry of Land,Infrastructure and Transport(MOLIT),Korea.It can be concluded that the use of tdf fly ash as a mineral filler in HMA not only satisfied the mechanical properties,but also reduced the volume of the pollutants waste in the environment.

关键词： Asphalt mixture tdf fly ash Marshal stability Moisture sensitive TSR

Stable multi-wavelength thulium-doped fiber laser based on all-fiber Mach–Zehnder interferometer

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Chinese Optics Letters 2014年第11期12卷 56-59页

作者：张鹏马万卓王天枢贾青松万春明 National and Local Joint Engineering Research Center of Space Optoelectronics Technology Changchun University of Science and Technology College of Science Changchun University of Science and Technology

We propose and experimentally demonstrate a multi-wavelength thulium-doped fiber（tdf） laser based on all-fiber Mach–Zehnder interferometer（MZI） at 1.9 mm. Here a segment of 4 m single-mode tdf is pumped by 1568 nm fiber laser for 2 mm band optical gain. The MZI includes two cascaded 3 d B coupler. A segment of 3.5 m long un-pumped polarization-maintaining tdf and polarization controller（PC） are joined in the ring cavity to suppress the mode competition. Multi-wavelength lasers at 1.9 mm with wavelength number from one to four are obtained by adjusting the PC and the stability of output power of multi-wavelength fiber laser is analyzed.

关键词： tdf MZI Stable multi-wavelength thulium-doped fiber laser based on all-fiber Mach Zehnder interferometer

Time-Lag Effect of Dietary Fiber and Fat Intake Ratio on Japanese Colon Cancer Mortality

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Biomedical and Environmental Sciences 1996年第2期9卷 223-228页

作者： KEISUKE TSUJI EMIKO HARASHIMA YASUE NAKAGAWA GUNPEI URATA AND MASUO SHIRATAKA(Division of Applied Food Research, National Institute of Health and Nutrition, Shinjuku, Tokyo 162, Japan Dept. of Food and Health Sciences, fuculty of Human Life Sciences, Jiss Division of Applied Food Research National Institute of Health and Nutrition Tokyo Japan.

The daily intake of total dietary fiber (tdf) was evaluated from data of the National Nutrition Survey (NNS) in Japan for 41 years since 1947. An interrelationship between the nutrient intake, including tdf, and the mortality from colon cancer in Japanese people was calculated by a simple correlation coefficient and time-series correlation coeffcient.tdf intake per capita decreased rapidly from 27.4 g in 1947 to 15.8 g in 1963, and subsequently decreased by a lesser rate to 15.3 g in 1987. Fat intake increased rapidly from 18.0 g in 1950 to 56.6 g in 1987.The age-adjusted mortality from colon cancer shows a significant positive correlation with both the intakes of animal protein and of total fat, and the fat energy ratio. A time-series analysis indicates that the mortality from colon cancer was negatively correlated with tdf with a 15-27 year delay, the maximum correlation existing with a 23-year lag (r = -0.947). The tdf intake was less than 17.9 g in 1965. At the same time, the mortality from colon cancer increased rapidly. A fat/tdf ratio above 3.0 resulted in a rapid increase in colon cancer mortality.The non-adjusted mortality from colon cancer has much the same interrelationship with tdf and fat intake as the adjusted figures. It is suggested that the cause of the increased mortality from colon cancer in Japan is positively related to the increased intake of fat and protein. In addition, the decrease in tdf intake has accelerated the mortality of colon cancer after a delay of 23-24 years. The importance of fat/tdf as a nutritional criterion for the incidence of colon cancer needs to be better recognized

关键词： tdf Time-Lag Effect of Dietary Fiber and Fat Intake Ratio on Japanese Colon Cancer Mortality

Scaling all-fiber mid-infrared supercontinuum up to 10 W-level based on thermal-spliced silica fiber and ZBLAN fiber

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Photonics Research 2016年第4期4卷 135-139页

作者： Zhijian Zheng Deqin Ouyang Junqing Zhao Minqiu Liu Shuangchen Ruan Peiguang Yan Jinzhang Wang Shenzhen Key Laboratory of Laser Engineering Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes College of Optoelectronic Engineering Shenzhen University

We demonstrate an integrated all-fiber mid-infrared(mid-IR)supercontinuum(SC)source generated by a 1.95μm master oscillator power amplifier system and a single-mode ZBLAN(ZrF_4–BaF_2–LaF_3–AlF_3–NaF)fiber.The maximum average output power is 10.67 W with spectral bandwidth covering from～1.9 to 4.1μm.The single-mode ZBLAN fiber and silica fiber are thermal-spliced to enhance the robustness and practicability of the system.It is,to the best of our knowledge,the first high-power integrated compacted all-fiber mid-IR SC source based on thermal-spliced silica fiber and ZBLAN fiber.

关键词： IR SC mode Scaling all-fiber mid-infrared supercontinuum up to 10 W-level based on thermal-spliced silica fiber and ZBLAN fiber high MFA LMA tdf

Principle of uniformity of temperature difference field in heat exchanger

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Science China(Technological Sciences) 1996年第1期39卷 68-75页

作者：过增元李志信周森泉熊大曦 Department of Fngineering Mechanics Tsinghua UniversityBeijing 100084China

A principle of uniformity of temperature difference field (tdf) in heat exchangers is advanced.It states that the more uniform the temperature difference field,the higher the effectiveness of heat exchanger for a given NTU and C,.Analytical and numerical results on the uniformity of tdf and effectiveness of thirteen types of heat exchangers show the validity of the uniformity principle.Its further verification is given by the asymptotical solution of tdf in terms of a recurrence formula of heat transfer area distribution.The analyses of entropy generation caused by heat transfer indicate that the uniformity principle is based on the second law of thermodynamics.Two ways,redistributing heat transfer areas and varying the connection between tubes,are presented for the improvement of the uniformity of tdf and the consequent increase of effectiveness for crossflow heat exchangers.

关键词： tdf of heat exchanger uniformity of tdf effectiveness entropy generation.

轮胎衍生燃料在分解炉内燃烧特性的数值模拟与优化

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轮胎衍生燃料在分解炉内燃烧特性的数值模拟与优化

作者：季杰安徽工业大学

学位级别：硕士

“十四五”以来,党和国家就新时期能源排放标准提出更高要求,致力实现“碳中和”“碳达峰”的目标,水泥工业作为国民基础的产业,污染物排放位居前列,形势刻不容缓,因此,探究水泥工业的绿色化、无害化、节能化,成为新时期的重点,水泥窑... 详细信息

“十四五”以来,党和国家就新时期能源排放标准提出更高要求,致力实现“碳中和”“碳达峰”的目标,水泥工业作为国民基础的产业,污染物排放位居前列,形势刻不容缓,因此,探究水泥工业的绿色化、无害化、节能化,成为新时期的重点,水泥窑协同处理固废技术应运而生。分解炉是水泥窑的关键一环,具有物料悬浮、相变传热、燃料燃烧及碳酸盐分解等多功能。该技术通过在分解炉燃料中掺加部分替代燃料以改善燃烧效果,同时缓解一次能源枯竭来的能源危机,具有重要意义,tdf(轮胎衍生燃料)因来源广泛,高热值,燃烧速度快,具有独到优势。本文以某公司3200t/d的TTF型分解炉为蓝本,对部分结构进行相应简化和改造,使用CFD软件进行了建模和网格划分,采用Fluent中数学模型对炉内的气相湍流、对流辐射、颗粒运动、生料分解、燃料燃烧、NO产生排放等进行数值模拟。(1)首先对煤粉、tdf两种单一工况在炉内燃烧特性进行模拟。煤粉、tdf在炉内流场分布合理稳定,体现出良好的“两缩口三喷腾”效应,锥体和主燃室区域出现的回流区有利于物料的返混,提高生料的分解率,燃料性质不同体现在三次风大小差异上,煤粉(工况一)、tdf(工况二)的出口平均流速分为29.6m/s、27.0m/s;燃料燃烧较为良好,高温区位于燃烧器出口附近,燃料不同表现为高温区范围大小和温度峰值差异,工况一二炉内平均温度为1260.2K、1263.4K;炉内各组分(O、CO、CO、Ca CO、Ca O)等分布合理,工况一二出口CO含量基本为0,O出口平均浓度均低于2%,证明TTF适应不同品味燃料燃烧,CO炉内整体分布趋势和Ca O相似,均是自底向上逐渐富集升高,碳酸盐含量与之相反。工况一二燃尽度分别为95.37%、97.25%,生料分解率为85.07%、86.16%。结果证明,保证吸热量相同的前提下,tdf燃尽度和生料分解率较煤粉更高。(2)煤粉、tdf的六种掺混工况下流场、温度场、组分场均相似。炉内整体分布仅与分解炉的整体结构相关,替代燃料仅改变炉内物质数据大小。随着tdf掺混比增加,炉内平均流速降低,炉内均温升高。掺混比0及10-30%的六种工况下燃料燃尽度分为95.37%、95.87%、96.08%、96.32%、96.51%、96.79%,分解率为95.06%、95.87%、96.08%、96.32%、96.51%、96.79%,选取20%为最佳掺混比;O/CO气氛内tdf单烧炉内流场、组分场分布和空气气氛整体相似,温度场相较前者分布更加均匀,高温区域更小,燃料燃烧更加充分,O/CO气氛下生料分解率为88.71%。(3)煤粉、tdf单烧工况下出口NO含量分别为349ppm、132ppm,tdf掺混比0和10-30%下六种工况出口NO含量分为349ppm、318ppm、304ppm、290ppm、276ppm、261ppm,空气、O/CO气氛下tdf单烧工况出口NO含量为132ppm、109ppm。结果表明,tdf燃烧产生的NO含量更少;随着tdf掺混比增加炉内NO含量减少;O/CO气氛能进一步减少炉内的NO整体含量。通过对tdf在炉内燃烧特性的多角度的研究,表明分解炉作为良好的气固发生器,可以适用于燃烧不同品味的燃料,对实现废物利用化、能源绿色化具有重要的指导意义。

关键词：分解炉替代燃料 tdf 数值模拟掺混比 O2/CO2气氛

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磁电双层膜层间耦合的弹性力学研究

物理学报 2008年第5期57卷 3237-3243页

作者：曹鸿霞张宁南京师范大学磁电子学实验室南京210097

基于磁致伸缩相与压电相的本构方程,应用弹性力学模型,简要介绍了如何推导自由状态的磁电双层膜纵向、横向磁电(ME)电压系数.并采用相应的材料参数计算了La0.7Sr0.3MnO3-Pb(Zr,Ti)O3(LSMO-PZT),Tb1-xDyxFe2-y(tdf)-PZT双层膜中的磁电电... 详细信息

基于磁致伸缩相与压电相的本构方程,应用弹性力学模型,简要介绍了如何推导自由状态的磁电双层膜纵向、横向磁电(ME)电压系数.并采用相应的材料参数计算了La0.7Sr0.3MnO3-Pb(Zr,Ti)O3(LSMO-PZT),Tb1-xDyxFe2-y(tdf)-PZT双层膜中的磁电电压系数,具体分析了其与压电相的体积分数v、界面耦合参数k以及偏置磁场H之间的关系.分析结果表明,在某一体积分数vm下,ME电压系数达到最大值,且最大值与k成近似线性关系.由于tdf的超大磁致伸缩效应,tdf-PZT双层膜的横向ME电压系数可达1.9Vcm-1Oe-1,而LSMO-PZT的仅为165mVcm-1Oe-1(1Oe=80A/m).将LSMO-PZT中横向ME电压系数随偏置磁场H变化的理论值与实验结果进行对照,其界面耦合参数k为0.2.研究结果表明:优异的磁致伸缩性能、合适的体积分数、良好的界面耦合是影响ME效应的关键因素.

关键词：磁电效应双层膜 tdf LSMO PZT

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压电-磁致伸缩双层磁电复合材料的机电谐振

复合材料学报 2013年第5期30卷 244-250页

作者：曹鸿霞李敏张闯刘清惓王友保南京信息工程大学江苏省气象探测与信息处理重点实验室南京210044 南京信息工程大学电子与信息工程学院南京210044

基于压电相和磁致伸缩相的本构方程以及弹性体的运动方程,简要推导了一维机电谐振模式下压电-磁致伸缩双层磁电复合材料横向磁电电压系数的表达式。采用相应的材料参数计算分析了Tb1-x Dyx Fe2-y(tdf)-Pb(Zr,Ti)O3(PZT)双层磁电复合材... 详细信息

基于压电相和磁致伸缩相的本构方程以及弹性体的运动方程,简要推导了一维机电谐振模式下压电-磁致伸缩双层磁电复合材料横向磁电电压系数的表达式。采用相应的材料参数计算分析了Tb1-x Dyx Fe2-y(tdf)-Pb(Zr,Ti)O3(PZT)双层磁电复合材料的横向磁电电压系数与交流磁场频率的关系,以及复合材料的长度和压电相体积分数对机电谐振频率的影响。计算与分析结果表明,双层磁电复合材料在机电谐振频率处具有明显的磁电响应特性。当有效机械品质因数为50,在谐振频率55.2kHz处横向磁电电压系数达到峰值11.2V·cm-1·Oe-1,是低频下峰值(281.9mV·cm-1·Oe-1)的40倍。机电谐振频率随复合材料长度的减小和压电相体积分数的增加而上升。实验结果说明tdf-PZT双层磁电复合材料在机电谐振频率处具有显著增强的磁电效应,实际有效机械品质因数约为48。

关键词：磁电效应机电谐振谐振频率 tdf PZT